With the continuing development and progress of electronic technology, the current commercial electronic products are always designed to be light, thin, short and small with multiple functions and rapid processing speed while taking the convenience and practicability into consideration to comply with the life demand of the modern society. In addition, with the maturity of IC design and manufacture technique, the electronic products in the new generation not only have slim and tiny shape but also have processing performance which is several times better than the conventional products. Therefore, all kinds of digital data such as sound effects, images, and patterns can be processed easily by means of their great computing and calculating ability.
It is worthy to note that the design of the electronic products must take the heat dissipation problem in the operation process into consideration due to their much more complicated operation performance. The commonly seen solution is to provide them with better heat dissipation performance by improving their materials and mechanisms. If needed, a heat-dissipating fan is mounted in the electronic product to prevent the electronic products from excessive operation temperature.
In order to promote the performance of the heat-dissipating fan, the rotational speed of the conventional fan designed by the manufacturers is always thus increased when the temperature of the electronic product is raised so as to accelerate heat dissipation. The typical method is performed by detecting the temperature of the electronic device, and then controlling the rotational speed of the fan depending on the detected temperature via a fan controller. Generally speaking, the rotational speed of the fan can be controlled by using the voltage output or the duty ratio of pulse width modulation (PWM).
Besides, some manufacturers also provide the fans with several fixed fan-temperature curves such that the user is allowed to select one of them. As a result, according to the operating requirement, the user is allowed to select one kind of fixed fan-temperature curve so as to control the rotational speed of the fan to comply with the change of temperature.
However, there are still many problems in the existing control design of the fan. First, as described above, some manufacturers provide several fixed fan-temperature curves to allow the user to make selection. However, these predetermined fixed curves can not actually or completely reflect the actual operating environment where the user operates the electronic device. In other words, for the users distributed over the world, they can only select the existing predetermined fixed curves and can not adjust the fan to the most appropriate rotational speed to comply with the different environments where they live.
Moreover, the slight variation in machine constitution or slight inaccuracy in the manufacture process causes even the same lot of electronic products have different characteristics from one another, resulting in that the control process of the rotational speed during the practical rotation becomes non-linear. Therefore, it is impossible to adjust the rotational speed basing on the predetermined fan-controlling model.
Furthermore, the user is incapable of monitoring or determining whether the fan-controlling performance is identical to the setting of production. Therefore, the user is unable to know that the related control device needs to be replace or repaired even when the related device is damaged or deviated.